Так как памятник был сооружен в 1780 (из надписи на тумбе, с которой была снята плита), а сама плита сделана из "Tournai marble" из Северной Франции или Фландрии, а стиль и особенности изображенного доспеха также соответствуют этому региону (и не соответствуют дате смерти изображенного персонажа), то скорее всего плита была импортирована в 18 веке или даже позже (когда во время Французской революции разграблялись церкви и уничтожались надгробия знати) и переделана под новую гробницу

(Link)
Sir William Oliphant
1370
Aberdalgie Church, Aberdalgie, Perth and Kinross, Scotland

(Link)
Aberdalgie Church, monument of Sir William Oliphant
The chief feature associated with that burial place was an incised Tournai marble slab for Sir William Oliphant, who died in 1329/30. The slab, which is the finest example of its kind in Scotland, was removed to the modern church in 1904, where it is set within a recess on the south side of the chancel area. It has recently undergone careful conservation. Although the stone’s long exposure to the elements has left its surface badly laminated, the armoured figure of Sir William is still discernible, as are parts of the complex micro-architectural detailing of the tabernacle which frames it..

(Link)
Sir William's tomb is in Aberdalgie Churchyard, in Perthshire, within the site of the original church. The effigy is made from "Tournai marble" from northern France or Flanders.

(Link)
Sir William Oliphant died 5 February 1329/30 and was buried inside the church at Aberdalgie, where several generations later his family erected a large tomb in his memory

(Link)