You're gonna be waiting maybe 2 years or more then. Classic 3DS XL's still can not be found for under $100 most places. I've not seen one (in working order) on Ebay for less then $130 or so. The cheapest one I've found was the one I bought for $109 (nearly $130 after taxes) from a local pawn shop (and the damn thing was still on 4.3. Was super lucky I guess.

) So yeah, gonna be awhile son.
Not to mention it will be difficult to find a n3DS on 9.2 or less 2 years down the road and if you do find one, it's going to come a premium price because it will be considered rare for it's Gateway compatibility. You think 4.x 3DS XLs are getting hard to find? Just wait until n3DSes on 9.2 or less become rare!
There might be fewer gateway compatible n3DSes produced (in North America region anyways) then there was 4.x firmware classic 3DS XLs. Pretty sure the first batch will still be on 9.0/9.2 for USA, but that won't last long at all.