Table for Offset a/c number “GKONT” in FBL1N??

Hi,

I want to write a query and retrieve the vendor offset account number(GKONT) from tcode "FBL1N".

The information is available in cluster table BSEG-HKONT.

As BSEG table is cluster table and it has huge number of records, we do not want to use this table.

I checked in BSIK and BSAK, but couldn't able find the Offset a/c number.

Is there any other table which stores this particular information?

If not, what is the best way to retreive this information?

Kindly suggest me.

TIA

Regards

Seema