Those heads look pretty worn. +the "disclaimer" of the seller, i think the writing is on the wall. Even if you get it for $200, that machine doesnt look good and you will spend probably a significant amount of time and money on it. Replacement heads for that are also very hard to find. The heads and other parts for the TSR-8, 38, 48 & 58 are easy to find. You can do better with any of those other machines, here's my take in priority order.
TSR-8: Good machine, newer unit (last one made) you can get a good one for ~$500 or a little less in very good shape. Parts are relatively easy to find.
48: Solid and very feature complete, excellent transport and electronics. Harder to find thatn the TSR-8, they will ask you ~$700-800 for a unit in good condition. Parts are relatively hard to find. This is a heavy duty machine
58: Top of the line machine. Harder to find and when found in good shape can go up to ~$1000. Parts hard to find. heavy duty machine.
38: A lot of them in the market, most of them in bad shape, it was the entry level deck for 8 channels in the 80s. The design is simple and is prone to many issues given its low cost design. Needs probably more maintenance than the others, one in proven good shape will go for ~$400-$500, there are worn ones that you can buy for $200 or $300 usually in very bad shape. A lot of people dissassemble and part out these machines as they are worth more in parts than complete and not working. Parts are easy to find.
80-8: People that have units in very good shape dont let them go, it is an early design from 35 years ago, electronics show its age and the transport is basic. Parts are very hard to find and performance is not the best. Depends on what you want to do with it.
I've researched and owned the TSR8 and 48 and also own a 32 which is basically the same design as the 38 in a 2 channel version and it leaves a lot to be desired.
As the 48 & 58 are so hard to find and with budget in mind I will go with the TSR-8, i know that machine very very well and i think it is a solid performer with some compromises (like only one head) but the impact on that is mainly on calibration, taking that longer, but also simplifying it. You also need to think what you will be using this for, how foten and for how long you want to keep it, these machines are getting harder to find by the day (the ones in good shape) that is probably why you dont find some of them as people dont let them go. As for the prices, those are realistic amounts, some will say $100 for a 38 or $400 for a 48 in good shape, maybe 5 years ago or so, but nowadays the prices above are what they are going on ebay. Local deals and hidden gems still exist but rare as people are not stupid and go to ebay to research. Buying from a forum member is also a good idea as usually it's people that knows the machines and can give you an honest assessment on condition. I have bought parts from people in this forum and others over the years that otherwise would have been impossible to find or very expensive/risky on ebay or somewhere else. Hope that helps.
Felipe