You cannot print on a transparency so forget that. It doesn't work. A good stable vellum can be bought from Stahl's.
Further, hopefully your printer has a "media" selection control. ie paper/card stock/vellum etc.. Use a card stock or rough paper setting. Turns up the fuser so you get more toner.
"Toner Aid" is just an invented marketing term for "Matte Finish" spray fixative. You can get it at most craft and art stores.
Applying fix to the toner/art causes the toner particles to expand, hence making a much darker image. I use Krylon Matte Finish #1311 ('bout 5 bucks a can). Whatever you use make sure it does not block UV light. Read the label.
Yes you can,to my knowledge u cant print on transparency with a laser. but u can print on vellum. i use vellum and toner aid from silkscreen supplies. i do one and two color jobs nothing complicated. the vellum and toner aid works fine. i think i paid 6 dollars for the laser toner aid and 30 for the vellum. but the free shipping starts at 99 dollars. here is a link
Laser Printer Kimoto Positive Film, Laser screen film, laser kimoto film, laser film, laser silk screening film, laser screen printing film
Yo! Check this out Ultrafine Laser Film - Graphic Arts there it is bro.Did what you said on their site and they came back with the following: "787 results found for ultra fine laser film." Not going to search through all those choices but thanks for trying!