FWB 150 looking for info.

I visited the local pawn shop yesterday, they had an old fwb 150 in .177 cal. It is in exceptional shape, heavy barrel, heavy gun. They are asking 400.00. I found little info on the yellow. Is this a fair price? Is this a good gun? I know it’s a fwb, it is a good gun obviously, but is it worth this kind of coin? I saw on the yellow a reference to the tyrolean model, what does this designate? And i beleive it was stopped being produced in the late sixties? Thanks for any info.