If you want to have the chokes opened up then IMHO you won't harm the value. I like more open chokes as I hunt over a pointing dog and therefor have closer opportunity.
I'm no purist and have had guns restocked to fit me and chokes opened. you have a very nice Parker and it will stay that way regardless of weather you have the chokes opened or not. This doesn't hold true if you have Briley thin wall chokes installed
