SmokelessJoe-CAPS is nearest and the one that will not bring it in. The others a 3+ hours away, no worthwhile to drive there for a quart.
wasagachris I have. Its $90.00 for a quart. If the same (type) of product can be bought elsewhere that I am looking at, its $37.00 for a US Gal and comes in different colours.
POR15 dont actually say what their product is, just what it will do, as do many of these others.
I will try to get an MSDS for the other products and compare it to POR15 Whitecote.
Latex paint is latex paint, gloss is gloss, all I am trying to do is make a similar comparison.
I appreciate what you have all contributed to try and help here but my original question (regardless of urethane or whatever) has not been answered yet and that is:
Is there a substitute, by another name, that I can use. I have seen liquid plastic, plastic enamel, gel coat finish (I think gel coat finish might be what whitecote is). Most of these (particularly a homehardware beauti tone product) can be got in different colours, thats one difference between all of these and whitecote.