That's a fine jersey -- it's thin, so if you're in a cold rink make sure you wear something warm under it.
For elbow pads, player pads are going to be very bulky, regardless of the sweater you choose. If you're just starting out reffing, you'd be better served by wearing volleyball knee pads as elbows. I did 9 years in the ECHL and AHL wearing soft foam elbow pads.