2003 Honda Accord A/C recharge?

I am looking for advice on recharge of my 2003 Honda Accord Air Conditioning refrigerant due to reduced cooling. I am the original owner and to the best of my knowledge the system has never been recharged or serviced. I am located on the east coast. The specific question I have is it acceptable to have a shop other than a Honda dealership recharge the system or use an over the counter refrigerant? I understand the refrigerant needs to be the same type, however the labeling under the hood near the fill port specifically states use of Honda refrigerant only. I believe I have seen ETCG use over the counter refrigerant on older Honda’s in a previous video. Honda specifies this for just about all of the fluids used in their cars. The car has 340,000 miles currently and runs like a champ. I will take it to the local Honda dealer if necessary but would prefer not too due to numerous issues I have had in the past with there service department. I do understand the do’s and dont’s of working on an A/C system such as leaks, recovery, and repair prior to charging. I do not intend on further destruction of the ozone layer so don’t waste your time on a lecture I am just looking for my best option here. Thanks in advance.