Tall Vintage Handblown Vase - Chribska?

This vase needs a good cleaning but I have to come to with a good idea how to clean the inside without doing any damage. The vase is almost 60 centimeters tall and is, other than the dirt, in great condition. I put the small vase (I still need to identify this one and hope that it is no recent Chinese import) there for comparison.

I would date the vase to the middle of the last century.

Thanks for looking:)