What type of material is best when making a monster token bag.

How about this one:

http://www.spoonflower.com/fabric/1204844-cthulhu-fabric-by-melitacurphy

You should be able to make two out of a fat quarter.

Very nice but l live in the UK and the postage is out of the question.

I ended up using one of the FFG Star Wars dice bags... it might not be thematic, but it works beautifully, didn't cost much, and is stocked locally (South Africa).

its a Crown Royale bag for each of my Lovecraft games. They are perfect, have a nice feel, a drawstring, easy to open, and hide whats inside. Also, they come with some pretty good booze.

A UK member of BGG was making Eldritch bags a few weeks ago and they're a decent size, I bought a monster and clue bag. I think she charged about £5 each plus a few pounds postage. https://boardgamegeek.com/thread/1518673/feedback-new-project

its a Crown Royale bag for each of my Lovecraft games. They are perfect, have a nice feel, a drawstring, easy to open, and hide whats inside. Also, they come with some pretty good booze.

Sipping Crown Royale while traversing the globe to save the world? Yes, please.

I bought some cucu dice from Kickstarter and the bag that came with them was big enough to use as a monster token bag

https://www.kickstarter.com/projects/xuanhu/cucu-dice-custom-designed-dice-for-arkham-or-eldri

Thanks for your suggestions.

May I add another tip of the hat to Crown Royal bags. Can't believe how long I played AH before recalling the old "Crown Royal" dice bags of my D&D youth. It was a pleasure to supply enough bags for AH, EH and Elder Sign.