Thats a tough call dear blueshy25, there are something very much unpredictable in life.
You said she is close to you, that has three possible outcome, she treats you like a younger brother, a request like this will shatter the friendship for ever. Second option is, you can ask her which she will readily agree, as if she was waiting for this, on that case just showing might not be enough, she might ask for more of your time. If you dont agree, she might twist this request and being your ex colleague, she knows your office mates, they will keep smiling at you at your back. Third option is take whatever risk you want, buy something real costly and surrender yourself saying you have a dream to see that, this is the best option you had to offer a gift and asking for a gift of flashing.
There is always a fourth optin, let it remain as your greatest fantasy. People should have some good fantasy which are achievable but never achieved. In that way, this one fantasy will charge you to have a higher libido. But once you fulfill that, the same fantasy wont help you anymore in future. If you have money, take a trip to Bangkok, go to Patpong at night, there are plenty of girls with great racks with tag number. Find the one with best rack, take to your room and have sex using condom. I will assure you, not only a lot of them have great rack, Thai girls have the best vagina, with puffy mounds, you would love that. Even if you dont have sex, still can pay them and touch to your hearts content paying hourly rate. If lookign for a cheaper option, go to dance bars and find the one with good rack.
In your shoe, I wouldnot fulfill my fantasy, I also do have a great fantasy, I know I can fulfill that, but I dont do that, cause I feel great to have that fantasy.