Appreciating that players who still play "Legacy" rather than "Live" have pretty much lost the ability to use the tools we've enjoyed for years, I've taken it upon myself to create a very simple and lightweight replacement for the Market Data specifically.
This is still based on EDDN data, which does differentiate between legacy and live game modes. But honestly, not many people are running the market connector in legacy so the data may therefore be limited (or useless).
I've popped it on temporary website for now that I use for other purposes and it will give a certificate error. If there is sufficient interest then will host it properly and perhaps develop it further. Happy to take feed back.
If you find it useful and want to shout me a coffee, there is a donate link. Anything is greatly appreciated but by no means necessary.
Can find it here :
Source: https://www.reddit.com/r/EliteDangerous/comments/1154n9m/ed_legacy_market_data/