Custom fit flat response plugs are avialable in 15dB and 25dB models. They are usually molded by an audioligist jamming a special clay cr@p into your ear. Not fun.
My 15dB jobbies cost $220 about 7 years ago. If you want to still enjoy music the 15dB ones are the go as the 25dB models do change the sound/frequency response quite a bit. 15dB is enough protection to get you close to the safety zone for your ears. Most PA/Bands operate around 105-115dB. Obviously if you are going to stand right next to a PA stack plugs won't help and you should just leave the gas oven on and whack ya head in there later on...

Personally I never liked my custom fits that well as they were made a smidge too large on one plug and were not comfy for extended periods. I use them now and then but carry $35 E.A.R brand "Hi-Fi" 15dB plugs with me everywhere. They look like 3 tiered mushrooms and are very comfy. They sound very close enough to flat response and are very good fro the $$$ give em a try.
Oh also if you do need the 25dB models they are still flat enough in the speech range so that you can talk/yell at someone and understand the response. Foamies/gell etc are hopeless in this regard.