I don't think the spare parts you have were original the bike. The Suntour derailleur and shifters are a bit of an upgrade over the Shimano stuff that's on the bike. The Shimano branded downtube housing stop also makes me think the bike originally came with Shimano, that's a part that's unlikely to have been replaced. I'd guess most of those spare parts were taken off of a Fuji and maybe saved to upgrade the Tsunoda. Those Shimano stem shifters are pretty cool though.