I know someone who completed his masters in UTAR, later pursued his PhD in Indiana University.

So you should try. No harm. But, you should be prepared with GRE and TOEFL. And, to secure a scholarship is really hard nowadays. SG is cutting alot of budget and prioritizing their citizen.

As for Spore, I'm not sure, but should be fine, i guess.

US definitely boleh, as long as the local U has its accreditation. All the best