Importing Selective Lines From Multiple Text Files

I have many text files basically with the same data from different dates. I am trying to select specific lines from each text, one that includes ".txt" which is the date, ex: "2008_308" and one that includes the word "PIXEL" and the following 5 lines after that.

I found a very similar post to mine and someone provided the script using VB for the question. It works, but it was only for one text file. I would like to use it for multiple text files. The files are all dated, i.e. "2008_308.txt". Although some of the dates are missing.

This is the script, from another posting, for importing selective lines from one text file:

Sub test()
Dim fn As String, txt As String, delim As String, a() As String
Dim i As Long, ii As Long, iii As Long, n As Long, x, y
fn = "c: est.txt" ' ��Change here (File Path)
delim = vbTab ' ��Change here (delimiter)
temp = CreateObject("Scripting.FileSystemObject").OpenTextFile(fn).ReadAll
x = Split(temp, vbCrLf)
ReDim a(1 To UBound(x) + 1, 1 To 100)
For i = 0 To UBound(x)
If InStr(1, x(i), "txt", 1) > 0 Then
n = n + 1 : y = Split(x(i), delim)
For ii = 0 To UBound(y)
a(n, ii + 1) = y(ii)..........................