I don't think this is the best way to get new material produced , firstly the company would have to finance it and to do that they have to see that there will be a market for it that would return a profit and seeing as the company would have already explored this beforehand it seems quite unlikely that there would be enough of a market (or they might not be able to get funding for the project.) , secondly they need actual material.
Unless there is more in the manga there's less than a 10% chance (just a guestimate) that they would make an original work so without material to work off of they won't even touch it , of course I have not read the manga so I don't know if there is any more material or not.
Also you would need a couple hundred thousand people to sign your petition to get any sort of recognition , not to mention the fact that even then it would be heavily reliant on local interest (People actually in Japan) because merch would heavily influence profit , most of that is sold locally and even with overseas interest the amount of overseas fans buying merch would have to be huge for them to consider it , without that there is no way it would be made.
That being said , I am not against your petition nor your enthusiasm but realistically I just don't think it will happen ... at least not in the next couple of years.
The best method would be to find as many fans of the series as you can and get them to try gain more support by reaching out and then gauge the support , you could judge the possibility based on the results and then put forth a solid plan of action to get it made , rather than just rushing in on your own.
Of course that does not mean that your petition wont succeed , these are just my thoughts on the matter.