Good osu graphics tablets are actually the cheaper ones, because there is less latency. (General opinion)
Not sure if you still need an advice, but XPPen's drawing tablets are very cheap. They perform just as well as a Wacom, but much cheaper.
https://www.xp-pen.com/forum-2450.html
I use a XPPen Star G640 drawing tablet. Runs OSU well. No problems at all.
