While I was in Russia, I bought a couple of Russian dolls for my children.
The kind lady in the shop said that traditional matryoshka dolls have eight dolls so the one I bought for my daughter is an old fashioned one. The one I bought my son is a bit more ornate and comes from a Russian fairytale (although I have no idea which one).
Each doll was about £18 (but that is approximate as I converted from roubles). At the time, I did wonder whether that was an enormous ripoff BUT I do think there is a price to pay for convenience. I bought them in a shop off Nevski Prospekt which, as far as I can see, is broadly equivalent to Regent Street. In theory, I could have schlepped for miles to find cheaper dolls but I was only there for two days so it seemed rather a false economy.