I have a part number somewhere for Toyota fender mirrors that look real similar to the JDM Mazda fender ones at a fraction of the price. Somewhere..
If you though your RX3 badge was expensive, Genuine JDM RX3 fender mirrors will cost you a kidney, and only if you could find a set.
Great looking car by the way, I love white RX3's and personally I think Hot Wires are cool (would be even better if Bridgestone decided to re-make 330 Eagers) and if you go for a set of decent tyres on them you will end up with some decent grip. From memory I used to run 205's on the front and 235's on the rear, but that was back in the day when Bridgestone DID make eagers.
Also, I recently bought a Pillar mounted arial for mine from OZ, it's a repro but you couldn't tell the difference and I think I paid $25 posted, which was pretty good I thought. And it's chrome and shiney! (you did say you needed one right??)