I have a Sparco 3 point.. although most harnesses seem to be made by Sabelt (Sparco ones are) so they are probably your best and cheapest bet... think they are about 30 from Tweeks
Luke five point 110 3" straps - fantastic belt just a complete fatherless b4stard Child to do up !! Have a three point sabelt as well for the passengers, much easier to use but not as comfy
I'd thoroughly recommend getting a 5-point harness. Threes/fours tend to allow too much movement/submarining IMHO. Chris