Can anyone help with endpoint https://www.bricklink.com/BTpriceSummary.asp ?

[Huseriato]

I'm currently working on a small app getting the price guide. In first place I only found the API Endpoint described here https://www.bricklink.com/v3/api.page?page=get-price-guide - But this api endpoint is extremly slow and also limited in count of requests per day.

BrickStore seems to use the url mentioned in the title. Is there any documention for this url or is it just a url used by bricklink website anywhere else? I'm missing the ability to define a country code for orders shipped from a specific country. Is this possible to do so?

Or is BrickStore using https://www.bricklink.com/priceGuideSummary.asp and scrapes the guide from html? I've not fully investigated the source code.

Can anybody help?