Your search for "plug cap" revealed the following:
Lambretta Floor End Cap Set fo Series 3 LI SX and TV Scootopia 19950094 19950103
$19.99Lambretta Floor End Cap Set series 3 LI SX and TV by SCOOTOPIA INNOCENTI 19950094 19950103
Lambretta Grey Rear Frame Plug for Series 3 each
$1.89Grey rear frame plug for series 3. This will fit all models (4 needed per scooter) See fig. 9 in...
Lambretta rear frame plug grey series 3 CASA
$2.99Grey rear frame plug for all models Sold each, 4 needed per scooter. INNOCENTI 19955094 8001142 See fig. 9 in...
Lambretta Crankcase Side Fibre Washer Kit Set of 3 MBP0190S
$5.09Lambretta Crankcase side fibre washer kit (set 3) This is a set of 3 fibre washers for the crankcase side...
Lambretta Fuel Tank Cap Viton Rubber Seal MRB0814
$4.09This is MB's new petrol tank cap seal. Made in Viton to resist modern fuels with ethanol. MRB0814
Lambretta Lever Anti Vibration Cap 19062019
$0.99Lambretta lever anti vibration "cap", for cap and spring set (1 pair) INNOCENTI 19062019
KYTRONIK PiFi Universal Pickup Filter - CDI Add on - 7676747
$28.99KYTRONIK PiFi Universal Pickup Filter - CDI Add on -This robust addon, plug'n play, will "clean up" any pickup signal...
Lambretta Original Style Spark Plug Cap
$7.99Original style spark plug cap for all models. INNOCENTI 15017070
Lambretta Legshield Beading End Cap Set for Series 1 and 2 15050063 15050064
$16.99Lambretta series 1 and 2 top & bottom legshield beading end cap set by Scootopia INNOCENTI 15050063 15050064
Scootopia Lambretta Disc Front Brake i Cap
$12.99Scootopia Lambretta disc front brake i cap for TV SX and DL GP INNOCENTI 19744064