what is your chassis code? 133 or 134?
For discs you can get a conversion kit from many places, prices vary from around £400 all the way up to £2000 for race units. try SSP (or CIP1) as they have a decent kits. (SSP part number AC698000A is for 134 chassis code 1303's,.. do check your chassis code before ordering though as early 1303's had different mounts & suspension)
Forget highback seats, they are next to impossible to come by in PK as very few cars had them back then so you'll probably be better off jsut getting your originals redone. do note that ALL 1303s had high backs (or headrests) except the 1200cc 1303A.
Seatbelts are out of stock over here at the moment but we have been trying for over a year to get more made. again, SSP or CIP1 have sets but they are a little expensive.
Rims, as long as they have a 4x130 bolt pattern, an offset around 23-34 and a maximum width of 5.5 inches you should be ok. Thereare many designs to choose from and do keep in mind that original empis are VERY expensive and the chinese replicas are as bad as all the other el-cheapo rims available in PK. American racing makes a decent replica (US made) but the design is ever so slightly different than the original EMPIs.
