Hi
The OE does not say what bandwidth he needs, just a target price?
How about the Juntek JDS6600 or very similar JDS2900 - both go to 60MHz and are 14-bit res, or Hantek HDG2000-series with 16-bit res, or OWON AG1000s with 14-bit res ?
All are within the $500 and can be bought from Alixpress and likelyt Amazon, too.