I would pass on the FR-7 unless you are going to handload for it. The action wasn't designed for NATO pressures. It was designed for the 7mm Mauser. The FR-8 was designed for the 8mm Mauser so it is Ok for the NATO round.
I made myself a list a few months ago. I decided I just can't collect everything and I need to concentrate on specific items. I know going into a show what I'm after and if it isn't on my list, I don't buy it. It's worked fairly well for me. I'm not going to collect variations, only one of each type. Now if there is a real deal to be made I'll reconsider, especially if the second item is in better shape than my first. Hopefully in that instance I'll have the willpower to trade or sell the first.
I already have some things that I would not have purchased under my new system but I don't think I'll get rid of them. The day will eventually arrive when I have everything on the list and I'll want to start expanding it.
For now, I'm concentrating on WWI and WWII main battle rifles and their bayonets.