I know recycled hardly last very long especially with fast paced character advancing rapidly game sessions for when I would print out the needed blank or specific character sheets from my PDF's of them. I know HP Multipurpose 20 lb. 96 Brightness works pretty well as do those papers specifically labeled for say Laser Printers and the like... If you have a local Office Depot or similar store near you ask them how much enough paper, i.e. Laser Jet/Printer, for said character sheet would be and buy a few sheets for test purposes from their print department or have them print out a sampling of each type they have in stock.
I know for my on the go writings I like the Caliber double spiral bound notebooks from my local CVS because the paper is a decent thickness for hand written notations. so you cold also do the finger and thumb rub to see how thick it feels to you.
Note if you want really heavy paper you could look for some sheets of card stock at you local supply store.
Or laminate the sheets and use a fine tipped dry erase marker to make you changes just be careful of smudging it.
