The Gospel Magazine: http://www.gospelmagazine.org.uk/ contains some ministry by WTT and other info about him, after he left Brethren and rejoined the Anglican church.
See the following editions,
1865 -June; At that time WTT was still minister of St. Silas. The heading bears the subheading: BY WALTER T. TURPIN, M.A., MINISTER OF ST. SILAS, GLASGOW.
1865 - October: p. 488, there is to be found a review (not very favourable!) of the Gospel Magazine's editor as to WTT's "Spiritual Watchman."
1900 - November
1905 - July: p. 440, there is an article by WTT: "Himself". Luke 24:27.
1905 - November: p. 668, WTT is briefly mentioned with a very nice thought. It goes i.a.: Rev. W. T. Turpin (Eastbourne) followed with an able address. He remarked that the secret strength of faith lies in the fact that all is treasured up in a Person; not merely doctrine, but Himself, not merely deliverance but a Deliverer, not merely redemption but a Redeemer ...
1906 - November
1909 - March and August
1911 - September;
1911 - October; p. 664, you can find a poem by WTT.
1912 - October
1913 - February
1915 - February and March
1916 - October: p 495, there is a quotation by "the late Rev. W.T. Turpin."
1923 - November
1939 - November