I know there are stats for the Harlequin's kiss but I can't find any for the Harlequin's Caress, Flip Belp, or Holo Suit. Is there a supplement that has these? I need to gear up and fully Stat out a Solitaire.

DW has exactly one single Harlequin written up and statted - she's in The Outer Reach, on p. 62. You can find the DW iterations of Flip Belt and Holo-Suit there, but she carries a fusion pistol instead of the Harlequin's Caress.

IIRC Black Crusade's Tome of Excess has some more Harlequins, you might want to check that, it could be there.

A lot of Eldar's equipment can be found in RT books. Holo-suit is in "Into the Storm", AFAIR.

These are part of an NPC profile under "Vaiuri M'atua" and Troupe Master. Black Crusade, Tome of Excess P112 (and repeated on the next page). I won't go into full details and numbers as you'll need to check the book but a brief summary of what it does is below.

Flip Belt - Gravity isn't as effective on them.

Holo Suit - Works like granting a field save.

Also I don't think you'll find Harlequin's Caress since IIRC it only came into existence with some of the more recent 40k codices which FFG probably won't have had access to at the time of writing. I may be wrong on that but you may need to scratch brew this as a result.

Incredibly helpful. Thanks all.

In addition to these, you can also find several pieces of Harlequin equipment (and an example Solitaire) in Dark Heresy 2E's Enemies Within. In particular, the Solitaire is modeled as being an Untouchable specializing in anti-daemon abilities. Also it should be noted that some of the relevant gear is modeled differently depending on where you look:

-Flip Belt: Into the Storm (RT) gave you Hoverer (6) and +20 to Agi-based tests. The Outer Reach (DW) changed this to Hoverer (6) and a free reroll on Dodge tests. Black Crusade Core (BC), the Tome of Excess (BC), Fallen Suns (RT), and Enemies Within (DH2E) changed it again to ignoring difficult terrain and the free Dodge reroll.

-Harlequin's Kiss: Most sources from RT and BC just gave it the standard 1d10+8/Pen 10/Tearing/no bonus to damage from Strength. Enemies Within also gave it Felling (4), which would be comparable to Felling (1) in DW.

-Holo-Suit: The Koronus Bestiary (RT), Edge of the Abyss (RT), and Into the Storm modeled this as -20 to be hit with WS or BS and +30 to Concealment if the wearer is still. The Outer Reach changed it to a Force Field with PR 35, overloading on a 1 due to craftsmanship, and also counted it as armor worth 4 AP. Black Crusade Core, the Tome of Excess, Fallen Suns, and Enemies Within removed the armor component to be its own thing and made the field never overload, sort of like the fields on Terminator armor.

Additionally, if you want to be really nasty to your players in combat you could employ an Eldar Clone Field (also from Enemies Within) on the Solitaire. It grants an extra reaction available only for Dodge, allows another free reroll for Dodge once per round, and doubles your DoS on such tests.

I know there are stats for the Harlequin's kiss but I can't find any for the Harlequin's Caress, Flip Belp, or Holo Suit. Is there a supplement that has these? I need to gear up and fully Stat out a Solitaire.

Supposedly, the Caress part-phases the wielder's hand, allowing you to reach inside your opponent and poke vital organs.

It wouldn't noticeably improve the wielder's strength - I'd suggest that it essentially count as unarmed attacks, or at best not much beyond this, but grant them the felling and warp weapon traits (essentially ignoring the target's armour and unnatural toughness values) - either automatically or on a 'called shot' depending on your preference.

Nice. Good suggestions, thanks.