I had the two Syrian mixes from Rodipet. The Junior and Senior. They are good quality mixes and they state some ingredients but don't list nutritional quantities. But they are hamster experts and they have a good reputation. Our Syrian didn't like the junior mix, the senior one was better. The protein comes from dried crickets and silkworms and insects, but some hamsters don't like them lol.
I found the same on delivery. The last few times things arrived within 2 days. Someone else bought a rodipet house on Amazon uk and it took ages to arrive so it sounds like ordering rodipet things via Amazon isn't as quick (and costs a pound or two more I think).
Everything they sell seems excellent quality and the houses are great. Expensive though - you could make something similar out of shoe boxes cheaper