Hello,
I don't have a script build for this but I can make the script for this within a week. You can run the script 24/7 or can even put it on a dedicated server and let it run 24/7. In dedicated server there's very minimal chance for it to be closed. A VPS would be enough, they are very cheap but this is just a suggestion, you can just use it on your computer.
So basically the script will check your competitor prices (assuming you provide the ID/SKUs of your competitor and your ID/SKUs of the product to compare with) if your competitor has lower price than you then the script will update your pricing and will make yours lower (I will put a option where you can decide how much percentage you want it to be lowered, like 5% or 10% or so). I can set it in a way that it will check every 5 minutes or 30 minutes, whatever you like. The script will be made in Python and will be light weighted but will need Internet connection at all times as it communicates with the internet.
Let me know if I'm wrong in some place or if you want to change/edit something
Now regarding the budget, the script will cost you around 400 EUR and I will give you 2 months of supports, for longer support you can simply pay a small monthly fee and get it. However I will always be helping you whenever you need me.
Let me know if you have any questions regarding anything.
Regards
Aimash