is listed as C.I. St John the Evangelist Parish Church, on page 108 of PRONI's guide (the successor church) but as the dates start 1853 which was the founding date of Laganbank and >100 years before its successor across the river in Orangefield, Co Down, are the ones you are after.
C.I. St John the Evangelist Parish Church, Orangefield (Down diocese).
Baptisms, 1853-1943; Marriages, 1855-1901; Printed booklet on the Churches History, c.1970.
Digital Records CR1/129.
Baptisms, 1853-92; marriages, 1855-97. MIC583/4 & MIC1/320
Good that the registers have been digitised likely as colour pdf's as makes consulting much quicker and easier on the eye [not available on the internet, just internally].
Sometimes the eCat is worth checking too inputting references or keywords.
PRONI ref:
CR1/129*"Please note that PRONI does not hold the original records, but a digital copy is available in the search room for records listed below this reference number.
PRONI holds digital copies of the following registers from St John the Evangelist Parish Church: Baptisms, 1853-1943; Marriages, 1855-1901; Vestry Minutes, 1870-1914; Printed booklet on the Churches History, c.1970. The original records are still in local custody."
Seems a small church hall was opened 1937 in residential Castlereagh as an Extension and ran jointly until St John's Laganbank closed 1943.
Belfast News-Letter 31 January 1955
https://findmypast.co.uk/image-viewer?issue=bl/0000038/19550131&page=8Belfast Telegraph 28 January 1955
https://findmypast.co.uk/image-viewer?issue=bl/0002318/19550128&page=4St John's Laganbank (nicknamed St John's in the mud) had no remaining local congregation due to the increasing industralisation & was taken over compulsorily WW2 1942 & demolished 1943 as Belfast Corporation needed an extension to its adjacent Electrical Works. On demolition of the old church the Diocesian Council decided the title, endowments and furnishings (+ the £ compensation for the Laganbank site) were to be passed to the infant parish of St John's Orangefield, formed in 1937 (out of parts of Cregagh, Willowfield, Knock and Knockbreda) and it was to be known as St John's Orangefield and Laganbank. [obviously the registers passed too]
The first rector of St John's Orangefield parish the Rev G W L Hill was instituted 6 April 1946, having been curate-charge since the union of the congregations in 1943.
The 1st sod was cut for the 3rd St John's church which the congregation had been saving up for on 29 Jan 1955 to replace the small church/hall authorised by the Belfast Church Extension Committee on which construction work had started Oct 1936.
Belfast News-Letter 27 Oct 1936
https://findmypast.co.uk/image-viewer?issue=bl/0000038/19361027&page=11I didn't know the fine details before today's hunt of the newspapers.