"I really want to ride my ugly rusty TW."... yea those 87's... lol. Might be the fastest but they are the oldest.
There are Chinese exact copy carbs on eBay quite often, the cheapest from a scooter company in Europe. Those are an exact fit. I got a few as spares, never used them yet but others I know say they work great at sea level. At the time they were $135 new including shipping. There are others, dirt cheap, not a %100 exact fit but fitable. Search the forum on google site:www.tw200forum.com