Hello all!

After riding a mountain bike for 3 years, mostly on road, I've decided to get a road bike but I never thought it would be so difficult to find the right size for me. I'm 5'4'' and my leg inseam is 31 inches (measured with cycling shoes).

After looking at many models I decided that I want a Trek Lexa SL.
Lexa SL Women's | Lexa Women's | Endurance race | Road | Bikes

In my country bike shops don't have many models/sizes in stock so I could only try one bike so far, a Trek 1.2 on size 47.
1.2 | 1 Series | Performance race | Road | Bikes

Other than that other bikes were just simply too big I didn't even bother trying them.
The first time I tried the 1.2 it felt like it was a good size but the saddle height was not set at the right height because the owner of the shop didn't bother measuring my inseam. I went to the shop a second time and they took my measurements and set the saddle to the right height and I could feel that something wasn't quite right. I felt the weight of my body on my hands a little, like the drop from the saddle to the handlebars was a bit too high.

The shop thinks the Lexa on size 50 is the best size for me considering that on size 47 I will probably have a big drop between saddle and handlebars. However I can't stop thinking the Top Tube might be too big and I will end up feeling stretched on it. From what I read it is a bit of a problem for people with long legs to find a bike that fits well. I would like some suggestions as to what size I should get, 47 or 50?

Unfortunately there is no way for me to try any of the sizes. The bike will be ordered for me and the shop says they can't send it back to the supplier once they order it.

Would really appreciate any help and ideas. Thanks