12ga/20ga are the least expensive ammo options, and a 28"-barrel/vent rib/ 12ga with interchangeable chokes will cover-off all the requirements mentioned. Mossberg Maverick (Mossberg's own offshore-made 500) has a pretty bullet-proof reputation but I'd suggest you spring for an actual Mossberg 500 because I have a lot of time with the latter and none with the 88.
On other online gun marketplaces in Canada, you can find older Mossbergs (search under "Lakefield Mossberg") which are excellent guns, but may also be missing some of what I've suggested. Most are plain (not Vent rib) barrels, fixed choke/often FULL, they have a single action bar vs. 2. On the positive side, they're often finished nicer than new guns and I've seen some listed at less than $300 and sit a long time. I'd probably pick one of these over an 88 myself, but feature-wise a modern 88 might suit you better.
870s are always an option, look for an older Express (will likely have all the features). I still see some pop-up where the seller things it's still pre-2020=listed around $400. Deals are out there, I'd always pick a used Remington/Mossberg over a new Turkish-made gun but that's me.