HK P7 may not be the best for your wife
My husband has had many HK P7's. They are great guns, but as a women I found the grip to be to big for my hand because the decocking device is in the fron to the grip. Also, it takes a fairly strong grip to cock the P7.
As an NRA firearms instructor who trains many women, I would strong recommend take her with you to select her gun. She should be able to have a comfortable good fitting grip, be able to reach the trigger, and be able to work the slide. And she must enjoy shooting the gun. I recommend if possible that women shoot different types of guns. If she doesn't like shooting the gun she won't want to practice. There are ranges that rent guns.
So she might try our the Springfield Armory XD compact. It is reilablel, reasonably priced and has adjustable grips. it has the decocking device in the grip but it is much easier to engage. H&K has the P2000 which also has adjustable grips. This gun is direct drive meaning you pull it out and pull the trigger.
H&K has great guns. But I don't think the P7 would be my choice for most women.
Anyway, my husband has owned H&K guns for ever. So any questions you need to ask he can probably answer.
Have a great Day