Hello,
Yes, both boots are correct for the W113. The one is the split boot and the other is the correct non-split boot. The "two required per car" is a mistake. The only MB cars using two axel boots were pre-1956 The first three digits of the part number "110" also tells me it is the correct part for Mercedes W110 chassis. W110 chassis cars used the same diff configuration as the W113 pagoda cars. Prices are very good!