Good Day

I have several sets of Model Engineer articles about building model steam locomotives. Let's take for example Princess of Wales created by Martin Evans. My set is complete.
There is no assembly drawing of the beast. More, since the assembly holes are drilled at assembly, they are positioned on the individual parts drawing, but not on the general arrangement (which anyways is the outside view only).

My-hobby-store.co.uk, the official shop for the magazine is selling a set of 15 drawings for this model. From the description it looks like those are the copies of the drawings which appeared with the articles ans no further information is available. I would hate to pay $125 for a set I have.

Is somebody capable to help me with this information ? Where to go ?

B. Hamerski