How to update prices on the site?

Question

Drupal

In general, there is a site on cms drupal 6.15. The site itself is as old as mammoth fleas, there is nothing really about it. Yes, and education does not allow somehow to influence there without fear of destroying. And there is also a !!... excel document, which indicates the name of the item from the catalog and the price for it. And we need to somehow change them, while there are somewhere around 2000 positions. Handles through the admin panel and changing pages - very long and dreary, and therefore I want to ask - is there any way to optimize this? I have access to the hosting and admin panel of the site, but I just don’t understand what I can do in order not to break anything. In general, I will be glad to any suggestions. There is a database hosted by mysql, but even here it is not without problems, since it seems that there are also old positions, somehow hidden when the organization still had another site. In general, everything is difficult.