Prado WheelNuts

Hi - I hope some of you have a solution to this problem - and thanks in advance for any comment.

1 have a 120 series prado (with alloy wheels) and a camper trailer with prado steel wheels.
What I'd like to be able to do, is to put any spare be it steel or alloy anywhere. I don't particularly what to carry more than the 2 spares (ie 1 alloy and 1 steel)

Mowing the Steel to the Prado is not a problem However getting the right wheel nuts for fitting the alloy to the trailer appears to be a problem . The trailer has an imperial thread hence the prado wheel nuts are no good. The "standard aftermarket" nuts for alloys shafts are around 1-2mm smaller than the prado's and resulting in a bit of slop where the nut goes through the alloy and therefore not satisfactory.

Is anybody aware where I may be able to get the"right" wheel nuts or if they have another solution.

Thanks Terry