I'm looking for a couple of replacement ceramic lampholders to go in a disco lighting unit that's in for repair. This thing uses two 300 watt bi-pin halogen capsule bulbs, with a pin spacing of about 6.3mm as close as I can measure. They are straight pins, not the ones that are hooked over at the ends. The original holders are a 3cm square with rounded off corners, about1cm thick. The top face is covered by a mica square fixed by brass swaged-over tubes, which are also the mounting holes for the holder. At the top of one side, just below the mica square, heat resistant sleeved 'tails' emerge. The two fixing holes with the brass tubes, are on the diagonal, but offset towards one side, and the holes for the lamp pins are similarly offset form the centre, by the same amount, and in the same direction.
I have searched high and low on the 'net for this holder, but drawn a blank. Lots of places sell the standard round ceramic bases with tails attached, for 5mm pin pitch halogen bulbs, but no sign of holders for these bigger ones. I'm pretty sure that I did actually see them on just one site, but it was an American trader, and I don't suppose they would want to ship a couple to the UK at a worthwhile price. I found that one quite early on, but discarded it because it was a U.S. company, and I figured if they had them, others nearer home would too. No such luck, and of course, I can't find that same site again. So, does anyone know what the official designation of this style of bulb is, or a name or designation for the holder, so that I can be a bit more targeted with search strings ? Or of course, if anyone knows of a source for them ... :-)