(Disclaimer...I didn't go completely natural...I ended up getting a hit of something when they broke out the forceps.)
Yes you can! I delivered the twins 26 months after my c-section, and my doctor wasn't the least bit concerned about me wanting a VBAC. As mentioned, finding the right doctor/hospital to support you is huge. You'll also need a little bit of cooperation from your babies...usually Baby A has to be head down for you to be allowed to attempt a twin vaginal delivery but it depends on the doctor and hospital.
There might be certain things they ask of you since it is a twin VBAC...my doc/hospital wanted to have everything ready to go in case it turned into an emergency c-section for any reason. I had to deliver in the OR with an OR team there and ready to jump into action. I had to have the epidural catheter in place once I got to 6cm even though they didn't put any meds into it...that way if they needed to do a csection they could have me numb almost immediately. It wasn't at all the calm, serene birth I dreamed of, but it was WAY better than a csection
Good luck! I hope you are able to have the birth you want!