Yes, it's the same for me, and fir has the same i as in the word it.
Thinking about it now though, I find there isn't a match to sound and spelling across all ir words in my Irish accent. (Maybe this is because they are pronounced the same in non-rhotic accents so room for variability?)
So, for example, I spell the word girl, but pronounce it more like gurl with the same vowel as fur. Similarly, I don't use the same vowel sound for fir and bird.