Rabbi Chaim Pinchas Scheinberg z”l on Shopping for a Pesak
I had a vague recollection of a pesak by Rav Scheinberg z”l on “shopping” for a pesak halakhah. A little searching on the internet found the source. The following is from the book Divrei Ḥachamim, p. 290.

Trans.: I heard in the name of Hagaon Rabbi Chaim Pinchas Scheinberg, that there is no prohibition to go to a second posek (rabbinic devisor) after one has received a pesak (legal decision) from a first posek (even if he is searching for a lenient opinion). The source is from the Arukh ha-Shulḥan and the Responsa Beit Hillel (YD par. 242:3), that this ruling (that one shouldn’t ask for a second opinion-MM) was applicable during the earlier generations when they didn’t have a definitive pesak. It goes without saying, that when one received a pesak from one [authority], he was unable to go to a second [authority] for his pesak, but today, when all of the laws are explicit in books of halakhah, there is no prohibition, even to go looking for a lenient decision in a situation when it is explicitly forbidden. (It is obvious that one should ideally ask permission before doing so.)
Here is a sourceshhet that I made for a class a number of years ago. Caveat Emptor.

March 21st, 2012 at 11:10 pm
by using the term “shopping” it sounds like there is payment involved and i am sure that you do not mean to imply that.
March 22nd, 2012 at 4:40 am
There is obviously no payment involved and there was no intention to convey such a thing, Although that has been known to happen.