Just had a look for you in the R182 and TR182 manual and it is the same, overhaul no, to be replaced every ten years.
I looked into it ages ago and I believe the Makers give no such life, rumour was the CAA/EASA were looking at going back to the on condition state on this, as said earlier the Cessna 152 and 150 have the same belts, one is on condition and the other is lifed, simply because the belts were missed out of one of the manuals.....
If an aircraft is used for 1000 hours a year then over 10 years you can see it, if its used for 50 and is hangared then the other way is sensible, again this used to be down to the engineers judgement and the system now just sucks, we even used to proof load test them.
Back to your's, read this, if you can ask the manufacturer of the belt if they have a life on them, then para 4 may help you, you might be able to go by the original manufacturers life and not Cessna's
see
http://www.caa.co.uk/docs/33/AIRCOM200918.pdf
The belt won't be made by Cessna, look on the back of the lap buckles, it will normally have the makers name on it, Pacific and Amsafe both have repair facilities in the UK, of which I have listed in posts above. Again it is down to your maintenance facility if they are happy with this and you may find they will want to clarify it with their Surveyor.