First of all, you won't get a 180 section tyre on a standard SV wheel! Correct size is a 160.
Second, £214 sounds a bit steep for Storms, I'm sure you could get them for around £190 ride in/out service (maybe less)
Edit: From Busters a pair of Storms for the SV is £155.
http://www.busters-accessories.co.uk...&tier3url=Avon
Hovis how much does your bloke charge for fitting?