Pure Methylcellulose Powder (1 lb) 100% Pure, Food Safe & Vegan-Friendly, No Emulsifiers or Mix-Aid Chemicals https://www.amazon.com/dp/B075Y19W8N/ref=cm_sw_r_cp_api_fab_HW0CFbXAB5JP2

It is a specialty ingredient so it makes sense to me that it’d be a bit expensive. One purchase would probably last a while.