Replacement Rockster front fender / mudguard

[College]

Front fender / mudguard on my Rockster is broken again! I think the tyre tread picks up stones and then crushes the fender from the underside, as there is only a few mm clearance, and pops the top surface. Done it twice now. Does any one know if any firm does a replacement mudguard / fender? At over £100 for an OE part would like to see if there is an affordable alternative. Second hand rockster ones are like hens teeth and the one from the standard R1150R to my taste is a bit yukky looking. Will an R1100S one fit a Rockster? Any ideas?

[riceburner]

R1100S will fit perfectly (it's the same thing basically).

Where are you riding that you're picking up stones big enough to catch between the mudguard and the tyre? I thought there was more clearance than that!

What tyres are you using?

[College]

Thanks i'll look out for an R1100 S one.
I live about 1/2 mile off the main road down a gravlled lane where the stones are upto 25mm across. Tyres are standard road tyres , not knobblies, which you would have thought would not pick up big stones. But the stones are sharp and angular so they could get stuck in the tread. I guess I will have to take it a bit faster so centrifugal force throws them out before they can get trapped underneath!

I am not sure what else could be causeing the damage to the mud guard - the crazing / pop marks just seem to appear?