I stand to be corrected, but when I was making enquiries for my 1972 I was lead to believe they were unique to Mog and hence subject to the usual Morgan Mark Up pricing.

"Y mae dafad ddu ym mhob praidd"
1972 4/4, 1981 MGBGT, 1984 FLHT1340, 1980 XLH1000, 1990 ZX10