What make and model is the turntable anyway?
DOn't try to read too much into the part number. Chances are good that the part was custom wound for whoever made the table, and the actual brand may not be available to you as a part. Not saying it isn't, but good chance it is not. Point is it is real unlikely the transformer is an off the shelf item. Turntable company goes to transformer company and says, make us 25,000 transformers that take 240v in and make 24v center tapped out at 750ma. Or whatever. And they say, OK, we'll do it.
Let's consider the problem. You have the old part and the turntable, so we can find out some things. How many secondary wires are there? And if they are intact windings, how many windings? The resistances won't tell us much, but you can find out what is a center tap and what isn't.
There will be power for the motor, and power for the control circuits, and power for the USB interface. SOme of those power sources may be shared. You should be able to find where the AC from the transformer goes, and I expect it will go to some rectifiers and filters. You should be able to spot if it uses split supplies like +12 and -12, or a single supply like +24. Are there three-legged voltage regulator ICs? You might have 24v for the motor and 5v for the logic, or even 3.3v for a processor - look for regulators.
Look at the main filter caps. If you see 35v caps, probably expect 25v tops for the supplies. REgulators like a few extra volts of headroom to regulate down from, so if there are 12 regulators, then 16-20v going into them sounds average. If we can get an idea of the DC involved, we can easily calculate what the AC would be to create those DC voltages.
And one thing in your favor is that it probably doesn;t have to be all that close. If all the operating voltages are regulated - likely - then as long as the input voltage is high enough for that couple volt headroom, but not so high as to cook the things, you should be OK.