A good finish varnish for canvas?



Hi all again, i paint with com-art over canvas or mdf panel,,,,living in costa rica is hard to get art supplys,,,so wondering if somebody may recomend me a good gloosy final varnish that i will have to import from usa....and stop using the poluretane for wood (floor) i actually use... Lol....i just apply it with a soft brush, well diluted...and everything is ok...but you start having the yellow look of all this barnishes....be expecting your coments,,,,and thaks in advance.

probably the only way to make the cost workable is with a 2k automotive clear but you need the equipment to shoot it Othewise you are stuck with Cans of spray which in the long run are EXPENSIVE I use poly on the funiture I build but I spray it also It really depends a lot on what you want as far as quality and durability
I have started using brush on varnish in my airbrush. I use a mixture of 30% matt and 70% gloss mixed with water so that it can pass through the airbrush. I use Reeve's. It is some of the cheapest available in South Africa. I do not want to drag a brush over my airbrush pieces but don't mind doing it over my brush work.