Just to throw out a number, I'd think that you should be able to get a nice late 20's True Tone alto in the $1,000 +/- range.
Value largely depends upon the condition of the individual instrument (especially the horn's finish and whether it's original) and its production year. That is, I'd expect a 1928 Buescher in prime condition to be a bit more expensive than one in similar condition made in 1924. That said, the cost difference will most likely be a few hundred dollars...not thousands.
As a rule of thumb, the most expensive Bueschers are typically the Top Hat & Cane model. After that, it could be a toss-up between the Aristocrat and New Aristocrat depending upon the horn. (Of course, fewer New Aristocrats were produced.) True Tones normally go for a less expensive price than the other models. As I mentioned before, 1926 is an important date for True Tones. Typically, True Tones in good condition produced in 1926 and after are in greater demand than True Tones made before 1926. Then, I'd expect very late True Tones made in the early 30's to be more expensive -- and are harder to find -- than late 20's True Tones.
The best thing, I think, is for you to do some on-line comparative shopping. www.junkdude.com
, and www.worldwidesax.com
are several excellent places to start. One problem with vintagesax.com is prices are not listed for some of the more expensive horns. However, you can email Gail (via the vintagesax.com web site) for price quotes. Also, Google "Buescher Sax" and you might find additional on-line shops that sell vintage Bueschers. By comparing horns & prices in this way you should get a feeling for Buescher price ranges very fast.
Not to beat a dead horse, but I'd suggest that you set aside the series numbers that you got from saxpics. They are helpful within the context of the historical comparisons on his website. However, most Buescher players and sellers do not use those terms. Rather, most of us go by the Buescher model name (such as True Tone, New Aristocrat, Aristrocat, Top Hat & Cane) and the serial number/production year. Dr. Rick's serial number chart is helpful in translating serial number ranges to production years.
In my personal experience with True Tones, I am much happier with late 20's True Tones than with ones from the early 20's. Intonation is better, the front F key is important, and late model True Tones seem to be overall better horns.
If you're serious about getting a good True Tone I'd suggest that you focus on the production years of 1928 or 1929, see what you can find, and the prices for those horns. 1928 & 1929 were superb years for True Tone production. This is the True Tone in full blossom. It's my impression that most True Tones produced in the early 30's have been grabbed by collectors. I have not seen many for sale.