Thanks all for the advice.
@deadkenny: I am using a SRAM quickview mounted over the stem like so. I have a short stem so the mount protrudes slightly behind the stem topcap. I do like to look at the ride stats while riding especially on long rides. Right now I am putting it in the pack. I am keeping an eye out on eBay for faulty units to cannibalise but nothing so far.
@petrieboy & @sajama55: I have considered that, but would be nice to be able to repair it since I have two mounts on two bikes. I don’t want to have to remove the (SRAM quickview) mount everytime I want to use it on a different bike.
@iolo: I was not expecting that to be warrantied, but threads on the Garmin website suggest that it has happened.
@hotter: looks like someone managed to successfully use Sugru. I might just give it a go.
@STATO: I don’t see such a kit on their website, but I’ve emailed them to ask.