Broken Cam Posts on Older Revolution

I recently purchased 2 used Revolutions from a friend of mine. One of them is an 2008 Model (last 3 of serial are 808) and one of them has NO Serial anywhere that I can find. I was told it was an 07' model. I was going to take them into a dealer to have them looked at for a hull warranty replacement/prorated replacement. The dealer asked if I had both serial numbers for them to verify, but for the life of me I can NOT find it on the one kayak. My other Hobie has the serial number around the rear of the hull near the drain plug.

Is there a place that I'm overlooking? maybe there was a secret location of the serial numbers on the older Revolutions? My dealer didn't know much about the older kayaks to help me look. Anyone have any Advice to help?

Also, any idea what cost I'd be looking at for a 2nd Owner Prorated Hull replacement? Is it like a percentage, or what?

Thanks a lot for any advice/suggestions anyone might have.

UPDATE:

So I contacted a dealer. Sent them the information and some pictures and they returned a prorate of $550 (400 for the hull + 150 shipping) for the 2008 and $925 for the 2007 model. So I got the 2008 hull ordered and decided that I'll repair the 2007 myself (3M DP 8010). Since I could just buy another used Hobie (With drive and accessories) for less than $1000, there wasn't much reason to replace just a hull for that much. I know I can do a decent repair and get at least a few years of life out of it.

Overall I'm happy with Hobie's service and the cost was fair. Not quite what I expected from what I read on forums (the 4 year warranty only covered outbacks and adventures). I can't wait to pick up my new hull and get it slimed!