In books of Bengali Wikisource, Bengali numbers are used as page numbers. For front matter pages, similar to roman numerals, Bengali currency numerals are used in old books.
Example having both types: https://bn.wikisource.org/wiki/নির্ঘণ্ট:গৌড়রাজমালা.djvu
So provision of these two types of numeral system is required for pagelist creation.
General Bengali numerals follow a decimal system ("0123456789" = "০১২৩৪৫৬৭৮৯") and thus adding support for "beng" numerals from the ICU, in a manner that the change from T268906 allows use of "thai" numerals, would suffice for this.
Bengali currency numerals, on the other hand, follow a hexadecimal system as follows:
i=৴
ii=৵
iii=৶
iv=৷
v=৷৴
vi=৷৵
vii=৷৶
viii=৷৷
ix=৷৷৴
x=৷৷৵
xi=৷৷৶
xii=৸
xiii=৸৴
xiv=৸৵
xv=৸৶
xvi=১৲
xvii=১৴
xviii=১৵
xix=১৶
xx=১৷
xxi=১৷৴
xxii=১৷৵
xxiii=১৷৶
xxiv=১৷৷
xxv=১৷৷৴
xxvi=১৷৷৵
xxvii=১৷৷৶
xxviii=১৸
xxix=১৸৴
xxx=১৸৵
xxxi=১৸৶
xxxii=২৲