Referencing Tom's irony, unless it's seriously going to be a joke DO NOT just get it, put it on out of the blue then lob it out with a flourish. Too many ways for it to end badly to list here, including many we've done ourselves.
I'd go about this a little more methodically, abeit I am a bit OCD.
First, the chastity kink itself. There's a whole spectrum of chastity from locking up for a few hours for kinky play then getting out for a grand finale, to 24/7/365 locking and a permanent goodbye to orgasms. Where do you honestly see yourself on this scale?
Second, your wife. You say nothing about her but you imply that your lives at the moment don't include kink. Any kink, I would argue, needs careful and diplomatic broaching, and chastity is a little off the beaten track (probably). Deploy your communication skills to see what she thinks - and tell her what she'd get out of it herself (if you have no idea, that's an issue right there).
Third, the device. All sorts of designs, and several materials. You need to do some intimate measuring to avoid your cage either falling off or turning your junk into purple/black junk. Try somewhere like this: https://lockthecock.co.uk/blogs/chastit ... -right-one
Fourth, related to first and second. Are your plans to keep the cage and activity in the bedroom, or do you want to embrace other, related chastity kinks? For many of us it's about reinvigorating our sex lives, but also about giving away power. This could be giving her the key during sex only, or it may be taking orders during sex, or chores around the house outside of sex. If you're thinking submissiveness, how does she feel about that? In my own experience, to say my wife was cool on chastity and cages is the world's biggest understatement. It wasn't until she felt she wasn't under pressure to be some sort of bedroom Obergruppenfuhrer, and she saw that my helping around the house was a serious and permanent commitment, that she settled in and began to enjoy things.
It's worth mentioning that giving power to your wife and embracing a little submissiveness isn't about giving up manliness and becoming some sort of sissy (unless that's what you want). One of the reasons I embrace submissiveness at home and in bed is that it gives me an escape from senior management pressures and responsibilities at work, dealing with staff, legislation and large budget decisions. Plus I am a bit kinky
Enjoy, but think it through.