These are known as the TRX wheels which are metric sized. You must use tires specifically made for these wheels and they are not easy to find. They were great tires in their time. Stock for this vehicle is 200/60-390. Unless you have a nostalgic reason to keep these wheels, you are probably better off buying wheels and tires using English sizes. http://www.michelin-passion.com/passion/front/templates/affich.jsp?codeRubrique=43&lang=EN
A BMW OE 15" wheel from an E34 5-series ('89-95) or E32 7-series ('88-94) will fit without modification, use your old lug bolts, and take a 205/60x15" tire perfectly. They are commonly available used for around $200 a set or slightly more depending on the style. Decent tires in that size are less than $100 each. Alternately, a complete new set of 15" or 16" wheels and tires from Tire Rack would cost still way less then four new TRX tires.
The only place which sells the original Michelin tires for metric BMW rims is Coker Tires. They purchased the mold from Michelin years ago and can reproduce them. Unfortunately, a set of 4 will run around $1,450.00.
Tire technology has really come a long way and I would recommend not using the TRX tires unless this is just a garage queen and you want it to be period correct. Otherwise there really is no reason to use them.
Having owned an '83 533i from new, I'd disagree these were great tires. In fact, my evaluation is that they are totally traction free.
You say they ARE traction-free?? I presume you're not still running on a 27 year old set of tires...?
