Even though "meila" מעילה  does not seem to have wide application because meila is associated with sacrifices. still it is applicable when it comes to nedarim (vows) and herem. (excommunication). [Meila is using a something that has been dedicated to the Temple for personal use.]  

This is the subject of an argument between the sages and R. Meir in the Mishna, but the law is like the sages that meila does apply to nedarim and Herem.

 The herem that the Gra signed is still applicable. And one that transgress it would have the law of meila applied. So what is that law? E.g if one has an animal dedicated to be a sacrifice, and then uses it to plow. He has to bring a guilt offering and pay to the Temple the amount that that animal is worth plus a fourth. [It is called a "fifth" but it means a fourth. That is a fourth of the whole value added to the whole makes five parts.] 

That is to say: there is no benefit that can be derived by ignoring the Gra. Like the Gra noted that he is hinted to in the Torah in the verse אבן שלמה יהיה לך --ראשי תיבות אליהו בן שלמה You must have a perfect measure. The first letters are the same letters as Eliyahy ben Shelomo. [This goes in accord with the idea of the Gra that everything and everyone is hinted to in the Torah.] 

The hint that I noted here is אבן שלמה יהיה לך = אליהו בן שלמה יהיה לך   To follow the path of the Gra.