I primarily use Tamiya spray cans for top coating, I've got their Flat, Gloss, Semi-Gloss, and even an odd can of Pearl Clear that I picked up for some reason, on my workbench. Just took a look downstairs, I've even got a few leftover cans of Model Master flat and gloss top coat too, but I'm guessing they don't make those anymore either?
At some point I plan to try the Mr. Hobby series of top coats. I've been impressed with their primers, called "Mr. Surfacer" followed by a number indicating fineness. They appear to have a series of clear finishes called "Mr. Super Clear" and "Mr. Premium Topcoat." My LHS carries many of their products, but it appears they are on Amazon too. Another possibility is to see if there are any Gundam/Warhammer/model figure stores near you--many of them carry some hobby supplies due to the rise of anime and figure modeling with those communities. I recently discovered Citadel shade paints at one of those stores, it's like a pre-mixed color wash that can be used for weathering.
It's hard to find a Japanese hobby product that doesn't work remarkably well.
