Still, having played a decent amount recently, I don't think you can guarantee a Royal Flush in one afternoon of play. But, if you are on a short schedule for achieving a Royal Flush, I recommend Poker Squares.
Unlike Chinese Poker, I was able to find an online location to play Poker Squares. There are trade-offs here, though. The online version is faster shuffle and scores automatically, which can save time. Playing on own, with cards, however, allows you to play the "shuffle' or "switch-a-roo" variant, thus allowing you to shift the position of the cards, which is a huge advantage. If you have a droid phone, there is an app with the shuffle version.
I was able to get my second Royal Flush (this one in hearts) on the online game:
With Royal flushes in clubs and hearts under my belt, I don't see why I shouldn't try to get Royal Flushes in all 4 suits.
