I have an old (1974) Gabriel shock dimensional data book. Is the 10' (foot ?) dimension extended, compressed, or midpoint of travel? I don't know that this will be of much help due to the age of the info. I would think that the shock manufacturers still provide this info but finding a store that has it will be the trick. I seriously doubt that it will be one of the national brands, maybe a surviving independent.
If you want to fill me in about requirements, I'll see if I can't give you some Gabriel part numbers that might help.
As to finding them already chromed, my guess would be that "it ain't gonna happen".