Thank you, I found a website with anti-pill fleece with lots of different patterns!No crochet blankets wont work and neither would felt. You want fleece blankets if you want to go with a liner rather then a shavings. If you want to go with shaving then aspen shavings are safe. Fleece is the only "safe" fabric because most chins don't chew it, but if chewed it doesn't come apart in strings that can get tangled in the gut or around limbs or neck. It also doesn't shred or fray so you can remove it before too much has been chewed and swallowed, a small amount should pass without issue but it can still cause a blockage if too much is swallowed. If they chew the fleece the only really option left is aspen shavings. You can also use kiln dried pine shavings but some people have said they have caused respiratory issues for some chins.
For fleece it depends on what cage you have and how much you want to spend. You can get fleece liners for cages like the Critter and Ferret Nations on etsy like here for example Where Every Pet is Unique- Safe Handmade Pet Supplies by PandamoniumPets There are lots of people that make them on etsy though, you just don't want any with anything inside it (other then more fleece), just in case the chin chews it you don't want them to eat something that can harm them. Cage liners for chinchillas | Etsy There are also some online vendors that sell fleece liners on their own websites Grand master chin supplier list the list hasn't been updated for years so some may be out of business now, also there are more vendors mentioned in the comments below the list.
You can also make your own fleece liners for much cheaper, instructions are here How to / DIY project listing Or you can just get some anti pill fleece (smooth not textured and doesn't pill up when washed) either from a fabric store or a lot of people just get cheap throw blankets at Walmart or other bargain stores (remove the string on the edging). If you can't sew you can use binder clips to attach the fleece to the cage.