While your upper may look ok don’t forget that the bits of the failed gears are spread through the whole drive because the lube supply is share with the upper & lower. I would try and see if there is a local shop that could do it, it might be tough because of parts & special tools availability. You could try to put in an insurance claim but it looks like an internal failure not from hitting an underwater object which would be covered. So you have some choices:
Local disassembly of upper gear unit & cleaning and checking bearings & gears and replace the lower with rebuilt unit
Use the SEI conversion kit to convert the Cobra to an aftermarket copy of the Merc Alpha drive.
From what I’ve seen rebuilt Cobras go from 2500-3000; the SEI kit is cheaper but the quality of the SEI drives is variable some good reports as some bad. I guess you could also use their kit with a used genuine Merc drive.
other options cost more as I said in other posts it depends on how much the boat is worth to you. The Volvo conversion is $$$ but good for repairability and resale, converting the whole works to a Merc (pull engine, replace transom mount & drive with Merc) is probably cost wise the same or a little cheaper than Volvo conversion but is a lot of labor cost unless you can do all yourself. If you had to replace the engine or rebuild the transom this would make sense otherwise it’s a lot of extra labor.