TLDR : Answer Summary
To extend a TR 60-day visa in Phuket, you typically need your passport, TM6 form, copies of these documents, two passport photos, and a fee of 1900 THB. It's also advisable to inquire about any additional documents such as the TM30, though for TR extensions in Phuket, it seems not to be required. The Patong office is open but does not handle visa extensions; you will need to go to Phuket Town for that. Generally, you should receive your passport back right away, but there may be scenarios where an 'under consideration' stamp is issued, although this is less common for TR extensions in Phuket.