leaking forks

So my fork seals are leaking (again!) barely two months after paying 140 quid to replace them. Mechanic says its the forks that are worn. But I'm not so sure a CB500 with 54K on the clock that hasn't to my knowledge been in a bad crash needs a new front end. So I measured the fork diameters with a digital calliper. The 37mm forks are measuring 36.7 to 36.8mm. Is that normal? Or is it a sign of wear?

 Any help would be appreciated.

I'm sure when I measured mine a long while ago they were measuring 37mm. I'd say try a new battery in the caliper you're using and/or fit the jaws around the stanchion then zero it there and remove the caliper from the stanchion and then close them and see if you get the same number.

The chrome itself doesn't wear - however the bushes inside of the fork leg (upper and lower) do wear though this shouldn't be enough to give enough movement to make the seals fail.

Thanks for the reply. You make  good point about the chrome not wearing. I suspect the bushings have had it and need to be changed along with a new set of oil / dust seals.

It's possible the mechanic damaged the seals when he fitted them, easily done if there are any dings on the chrome and they haven't been flatted off.
What usually happens to the bushes is that the teflon coating on the inner face starts to wear off.

I've bitten the bullet and ordered new fork tubes, seals and bushes. I got a second opinion from another mechanic who showed me where the forks were pitted and scratched. Possibly as mentioned above by previous botched job. Come next April, if I have to swap the bike for a >2007 one due to the new ULEZ rules in London, at least I can sell it in proper condition and get twice my money back.