Frank,
There is a Hardinge serial / date list on one of the Yahoo Hardinge group sites, the lathe group, I think. Although the serial number sequence included several of the different Hardinge machines (TLs, ESMs, TM-UMs, etc) in production at the time, it shows sn 23050 as the first machine built in 1945 and 24104 as the first machine in 1946. There is no way, that I am aware of, to tell how many BB2Vs were made in any year or in total.
If in good shape and with the tooling you describe, I think $800 is a very good price.
Your best bet for documentation, if any exists, is to ask for it here and in the Yahoo Hardinge mill group files. The smaller mills, such as yours, do not appear to have been made in significant numbers so it is likely that no documents were produced. Hardinge produced the TL lathe and TM-UM mill during the same time period (late 30s through the 40s) in significant numbers. No parts list for the TL is known to have been produced and operators manual for the TL and TM-UM, while helpful, are little more that a brochure describing the control's functions.
Larry V, who posts here frequently, is probably the single most knowledgeable person with respect to Hardinge machines of that era and their documentation.
Jim