Greetings again!
The site https://www.magiccardmarket.eu/, a market place for both commercial and private sellers, is quickly becoming the de-facto standard way to buy and sell magic cards in europe, cutting out the middlemen.
As it is almost the only relevant source of prices for me (even card-for-card trades at my local game shop are checked against "lowest price from an established (=more than 5 sells) seller from our country"), I once again tried to write an LHpi sitescript for it. They offer an [url]API[/url] to access their site that could be used to receive pricing (https://www.mkmapi.eu/ws/documentation/API_1.1:Market_Place_Information). For that I need to implement basic OAuth (https://www.mkmapi.eu/ws/documentation/API:Auth_Overview), and there's currently two puzzle parts missing from MA's api:
1) I need to get os.time() to get unix time and nonce to construct the authorization.
2) I will have to send https GET requests with an Authorization header. My attempts at finding a working version of luasockets dlls for lua52 were unsuccessful so far. As you already have ma.GetUrl in the API, I hope however you implemented it would allow to expose enough to add the Header to the request...

As they offer multiple prices

SELL (Average price of articles ever sold of this product)
LOW (Current lowest non-foil price (all conditions) )
LOWEX+ (Current lowest non-foil price (condition EX and better) )
LOWFOIL (Current lowest foil price)
AVG (Current average non-foil price of all available articles of this product)

this script could also profit from my FilenameOption proposal: with the price type and offline mode set through the filename, multiple price versions could be imported with only one query to their server.

Of course, if the only reason you delegated pricing to external scripts was the volatility of html-scraping, you might be persuaded to add a real magiccardmarket client to Magic Album. Interesting ways to use it include:
-having more than just one price column available in the grid, to see LOW and AVG at the same time.
-Creating an inventory and uploading it to sell cards.
-Building a Wanted list from the difference between a deck and the inventory.

If there's any more information you need or any help I can offer, please ask.