1925, Special ‚stamp-exchange‘ issue with four different russian stamps with black overprint and surcharge of new values incl. 15kop. on 1kop. brown/green on yellow, 50kop. on 1kop. orange/grey, 75kop. on 10kop. blue/brown perf. 11½ and 1r. on 3kop. red/grey perf. 11½ in a lot with about 40 stamps each mostly in pairs or larger strips, mint never hinged and scarce, Michel 9, 11, 12A and 13A, € 3.920,-- +