you can try cute pdf, but its not free   http://www.cutepdf.com/ pdf sdk

from their sample code you will be doing something similar to

Dim objMyForm

Set objMyForm = Server.CreateObject("CutePDF.Document")  'Create form object

objMyForm.initialize("FS20-001-12345678-12345678")          'Initialize object by serial number of the license

'Open an encrypted PDF form file from an URL with password 'cutepdf'

if objMyForm.openFile("ftp://www.ftpsite.com/Encrypted_Form.pdf","cutepdf") = false then 

    errorMessage = objMyForm.GetLastError()

end if

'Set some value into fields

nReturn = objMyForm.setField("Company", "Acro Software Inc.")

nReturn = objMyForm.setField("Address.1", "Company address")

nReturn = objMyForm.setField("Address.2", "City, State, Zip")

nReturn = objMyForm.setField("Product", "CutePDF Form SDK")

'Save completed form file into a new PDF file

objMyForm.saveFile("D:\CutePDF SDK\Forms\Form01.pdf")

'Save a duplicate copy

objMyForm.saveFile("D:\CutePDF SDK\Forms\Form02.pdf")

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which is your normal component usage