Help Need to know what rear callipers fit an '88 1100FJ

[nismo]

I'm just getting the GSX1100F I got a few weeks ago in a road going state and I replaced the rear disk tonight. That went a lot better than I thought it would but I went to bleed the brakes and the bleed nipple was so frozen I snapped it off

So I'm looking for a rear calliper but I thinking I should upgrade it as it will be easier to find something more modern here in NZ.

Anyone know what callipers are interchangeable with this?