CC for Engagement Ring

I am planning on getting engaged by the end of this year. My budget for the ring is about 10k, which I have saved throughout my degree. Originally, I was planning on buying the ring in cash, but then I realized there might be an opportunity to get points/cashback from credit cards as the place I am looking to buy it from accepts credit cards. My credit limit is not that high and given that I am in school, I doubt that I could get a limit high enough from my current cards or future cards to pay for the ring with just my credit. Given this information, I have a two fold question:

- first, would it be advisable to purchase the ring with a credit card and if so which card would offer the best rewards for this one off purchase

- second, if I apply for said credit card and my limit is 5k (assuming), could I prepay the additional 5k and rack up 10k worth of points or will the credit card cap the rewards at the 5k limit.

Thank you