More info at https://en.wiktionary.org/wiki/spiel . Pronounced as you (gp) spelled it phonetically because it's borrowed from German.
A few years ago, I used the word "Schmuck", and someone asked me if I was Jewish (I'm not). I didn't realize that "Schmuck" was also a Yiddish word until then. I looked it up, and I didn't realize that some Yiddish speaking people consider it to be obscene profanity! So now I use a little more sparingly.