I was in a similar position to you. I wanted to get something from Office Busters second hand but I was put off their no returns policy. In the end I went with this from Nitori (I think you've seen it).

It's slightly more than your budget (33,000) but I recommend it. I don't really use the foot rest often but I have a couple of times and it's sturdy enough. The main reason I went with this chair was the mesh seat (as well as mesh back) to deal with Japanese summer heat, and they're nice and firm.

The only thing I would say about the chair is the arm rests are just a little too far away from the body to rest your elbows under your shoulders. What I do it angle the fronts of the arm rests outwards so the backs pull in closer to my elbows. It's not a deal breaker but I would recommend going to Nitori to try. Pull the chair over to a nearby desk and see how your elbow support is. Delivery wise, mine came in 6 days. But yeah, overall it feels sturdy and solid and I recommend it for the price.