Keep in mind that the eGo is 3.3-3.4V, not 3.7V. If you want the same voltage, then you'll have to get another eGo bc there's really nothing else that has such a low voltage. For about the same size/price, I think you'd be much better off getting an Epower or kGo. Their both "eGo type" PVs, but their true 3.7V devices and both are affordable and give a great vape. Personally I prefer the Epower over the kGo/eGo/riva bc it's the only "eGo type" PV that uses removable non-proprietary batteries. Epower batteries cost $4-5 compared to eGo/kGo/riva batteries that cost $14-20, and they last a lot longer before they need to be replaced. Also everything is replaceable on the Epower so it's cheaper than the eGo/kGo/riva to maintain.
Like others mentioned, the eGo twist is also a good option. I have one and for how small they are, it does work surprisingly well for a VV device. I'm not a huge fan of not being able to remove the battery, and I hate the crappy/cheap chargers that eGos use, but I do still like the device and recommend it.
I have a SS mini V-tube that I use when I'm home and out, and I got the eGo twist to use while I'm at work bc I deal with a lot of chemicals and didnt want to mess up my SS V-tube. I like the twist bc I can use the same cartos on it that I do on my V-tube. When I first got my SS V-tube, I was just using my Epower at work. I like the Epower alot, but didn't like that I had to buy different cartos for each device. I use the 1.7ohm "Ressurectors" in a tank on my Epower and I use 3.0ohm SC XL cartos in a tank at around 5V on my V-tube. I really couldn't use the same cartos on both PVs bc 3.0ohm cartos are very weak on a 3.7V PV and using 1.7ohm cartos on a VV PV really limits the range of voltages you can use.
That's why I decided to get a twist and now I don't have to buy different cartos bc the 3.0ohm SCs work great on both devices.
I think you'd def be happy with a twist, and depending on what cartos you use on your Provari, theres a good chance you could use them on a twist too.
Keep in mind though that the twist is quite long. A 650mah twist is about the same length as a 1000mah regular eGo. I do wish it was shorter, but it's not the end of the world. I have a 900mah twist and I can still carry it in my pocket with a 3.5ml tank on it
