Slightly confused. They don't make a 4.85 and I don't think they ever have.
Current sizes are either a 4.8 a 5.3 or a 5.85.
Ribcraft did make a 5.45 around this age boat.
From the pictures and the engine size (4.8 is rated to max 60hp so I think this is ruled out)
I think it could well be a 5.45
I would message the seller and ask for a photo of the boat plate. This will tell you.
If it is a 5.45 then I have owned one. IMO. This was an incredible boat, punched way above its weight in terms of boat ride and performance.
Looks like a good setup, well worth a sea trial and a check out... Good luck!!