I've seen anywhere between £30 and £70 depending on condition. I think some prefer that 45 version with the sax, over the LP which doesn't have the horns, hence price gone up as more have looked for one.
Maybe not relevant but I'm sure I read somewhere some time ago that Dee Dee Warwick never liked the 45 mix as it didn't really seem to allow her vocal take the lead. I tend to agree for what it's worth.
I think you'd get £60 for NM in sleeve.