What information it has on how many drinks containers are sold in Scotland, broken down by (a) container (PET, Glass, Aluminium, HDPE, etc.…

The following table is from Zero Waste Scotland container data used to model a deposit return scheme (DRS) for Scotland.
Product category
Can*
Glass
PET
Grand Total
Alcohol
221,893,000
295,870,000
20,905,000
538,668,000
Soft drinks and fruit juice
364,637,000
24,888,000
332,522,000
722,047,000
Water
11,000
588,000
200,787,000
201,386,000
Dairy
228,000
10,058,000
91,198,000
101,484,000
Other
52,591,000
1,607,000
48,704,000
102,902,000
Grand Total
639,361,000
333,011,000
694,115,000
1,666,487,000
* Of the total drinks sold in cans, Zero Waste Scotland modelling assumes 99% are aluminium and 1% steel.
Figures are based on Kantar consumer panel data for in-home soft drinks, in-home alcohol, and out-of-home soft drinks, rounded to the nearest thousand. Out-of-home alcohol estimates are based on a combination of NHS Scotland’s estimates of on-premise alcohol sales and British Beer and Pub Association statistics. Due to the planned exclusion of HDPE from DRS, data on HDPE are not available to the same level of detail. Zero Waste Scotland is currently working with industry to improve estimates for all containers placed on the market in Scotland, using manufacturer and point-of-sale data sources.