I've convinced myself that the MINTLP uses IEC standard Lofgren A (Baerwald), which at 258mm results in 15.025mm. The Lofgren B IEC standard comes out to 15.422mm which might be the difference between the MINT and the VPI jig. It looks pretty close to a half a mm. The VPI jig wants more overhang which is consistent with Logren B.
Of course non of this solves your problem of 262mm spindle to pivot. Might I suggest you download Conrad Hoffman's program and print out IEC Lofgren A at 262 and compare it to your MINT protractor. I suspect your MINT is either 258mm or 259mm, since both of those numbers were used in the past. You could also print out a 258 and 259 and check those against your MINT and then you would be sure of what you have. Ultimately though you might consider using Hoffmans printout at 262, since that is you spindle to pivot distance.
Of course non of this solves your problem of 262mm spindle to pivot. Might I suggest you download Conrad Hoffman's program and print out IEC Lofgren A at 262 and compare it to your MINT protractor. I suspect your MINT is either 258mm or 259mm, since both of those numbers were used in the past. You could also print out a 258 and 259 and check those against your MINT and then you would be sure of what you have. Ultimately though you might consider using Hoffmans printout at 262, since that is you spindle to pivot distance.