Thanks for all the replies, comments and help guys, much appreciated
Mart (marto303, hero, legend and proficient rum drinker) & Ro (lotus driver & equal measures legend) took pity on me and took custodian of ol' red during the course of last week. We sourced two "OE equivalent" pumps, one a FAI pump from eBay sold by a company called Trechii and the other supplied by a local factor, Beds Batteries. The FAI pump was utter poop, horrible casting with myriad cracks and poor quality, on the other hand the Beds Batts pump looked good - really nice casting and good gear movement. To be fair to FAI, it looked like a rubbish pump sold in a FAI box rather then a proper FAI item. Mart and Ro got the good one fitted after giving the engine a full check over and it's all good now - strong oil pressure again & I'm back up for MIRA next week! Even managed to pop in to the charity event briefly to make a healthy donation to restore some karma!!
Huge thanks and a hearty recommendation to my good chums Mart & Ro - I'm forever in your debt!
Oh and an order has been placed for a dry sump system with SBD .............. Ouch.