There are Catholic Churches on the island so you should not have a problem finding one. Here's some info:
The Dutch side has Roman Catholic churches in Philipsburg, South Reward, and Simpson Bay. St Martin of Tours at 30 Front Street (Philipsburg) has services Monday and Tuesday at 6AM, Thursday, Friday, and Saturday at 6 PM, and Sunday at 8 AM. The phone is 599 542 5892. The French side
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