$400 will not get you too far.
If you want a nice lathe for doing shaft cleaning, retapering by sanding, ferrule replacement and tips I have something nice I built with a Taig compound slide on a tool post that slides and clamps along the frame. Mounted on a 6 x 40 inch board, frame is 8020 one inch square aluminum, with an adjustible speed motor and steady rests. You would have $200 left over for yourself too! Please PM me, you will like this deal alot I think.
The basic Taig 15 inch bed, motor, toolcarriage and is $400. But you can't work on shafts with it because it is too short of a bed, with ony 8 inches of room to work, it's made for machining little aluminum parts and that.
The bore on the standard Taig head stock is tiny (like 8 mm) so you need to upgrade to the $70 H100-06 headstock with the 0.59" bore 915mm), but then you need a $10 pully to fit the wided shaft on the spindle. A bigger bore headstock to fit a cue butt is $400 by itself (no a thing more). Oh and you still need a longer bed to work on the shafts.
A 36 inch bed could run $200 and they only come from the cue lathe makers (or whoever makes them), Taig doesn't sell them.
So yes a basic taig microlathe, is $400, bigger headstock and pully $80, longer bed $200= $680 new, no steady rests. Repair lathes sell very fast , and usually close to retail. They come up very infrequently.
The 700 setup above barely gets you in the door, there is so much more to spend money on. I know because after built the shaft and tip lathe mentioned first for just about $250 , I started to build a more substantial lathe with a 1.35" headstock, bigger steady rests , longer bed and even assembling it myself with some used asttachments it is going to be right under $1000 the way I want it.
This is why the cue lathe makers get and deserve the $1200-1500 for the lathes they sell that are "midsize". A entry level cue building lath with tapering attachments is 3K.
Send me you info by PM or leave a note here and I will give you first crack at the Taig shaft lathe with compound slide, it can send the cutting tool in any angle for a few inches of travel along, across or at an angle of the tip of the cue.