Postmark - 2x indication stamps Not to be Found + Returned to - Great Britain

United Kingdom:
2 marking stamps:
Estimated late 19th century / early 20th century.

1x "Not to be Found 498C"
Bronze stamp, height with handle approx. 8 cm, stamp base about 40 mm wide.
Handle repaired with iron wire, apparently long ago.

1x "Returned to"
Bronze stamp. Wooden handle.
Height approx 10 cm, print width about 40 mm
Top of the handle has been sawn off / filed down.

In used condition.
Patina appropriate to the age.

(several photos are mirrored)