Which model of SV do you have? My pointy measures speed with a spinning magnetic field on the wheel, so was not affected by a sprocket change.
When I changed my chain, I used a DID chain and sprocket set from a e-Bay, the whole lot cost about £150 at the time, but I did go for the best I could afford.
Top tip though, a chain oiler maintains your chain and allows for greater distances between changes. I use a
Tutoro Auto which is a simple and and elegant design, but other types are available.